North Transfer Station

Architect: Mahlum Architects

Owner: City of Seattle

Location: Seattle, Washington

Project site: Previously developed land

Building program type(s): Office – 10,000sf, other

The strict height limit prescribed by the neighborhood agreement to maintain their views necessitated an innovative structural response and careful planning of vehicular access. Image: Mahlum Architects

Seattle is the nation’s fastest-growing big city, with 18.7 percent growth over the last 10 years. It’s also one of the nation’s densest cities, with more than 8,600 people per square mile. With more people comes more waste, recyclables, and compostables—taxing the city’s aging infrastructure. To reach its zero-waste goal, Seattle needed a more efficient transfer station than the 1960s-era facility that stood on the site. On a typical day, the new station receives approximately 400 tons of various materials and is designed to handle up to 750 tons per day to accommodate anticipated growth. Integrating this large-scale infrastructure into a dense, low-rise neighborhood was the biggest challenge. Bermed into a sloping 5½-acre site between Lake Union’s recreational waterfront to the south, single-family residences to the northeast, and mixed uses to the west, the facility consists of two low-slung buildings on either side of a weigh-scale yard. The main structure comprises a 63,246-square-foot tipping and transfer floor, an administrative block, and a lower level for compacting and collection. The 10,000-square-foot recycling building allows self-haulers to divert materials from the waste stream, a function the older facility lacked. The challenge facing the design team was to replace the out-of-date facility with one that was larger and more efficient while meeting the demands of two abutting residential communities. The massing responds to the most stringent constraint: a building height limit of 78 feet above sea level—equal to the existing grade at the site’s top corner, enabling the hillside neighborhood to overlook the facility to take in lake and city views. Rooftops are clear of mechanical equipment, supporting photovoltaic arrays and greenery instead. In addition, the design incorporates queuing space inside the site to reduce congestion and noise impacts on the neighboring community. The mediation of industrial and human requirements is the station’s major achievement.

Additional information

Project attributes

Year of design completion: 2014

Year of substantial project completion: 2016

Gross conditioned floor area: 8,499 sq ft

Gross unconditioned floor area: 163,600 sq ft

Number of stories: 2

Project Climate Zone: ASHRAE 4C

Annual hours of operation: 3,328

Site area: 217,800 sq ft

Project site context/setting: urban

Cost of construction, excluding furnishing: $75,800,000

Number of residents, occupants, visitors: 105,413

Project Team

Engineer: CDM Smith, Inc.

Engineer - Acoustic: Greenbusch Group, Inc.

Engineer - Mechanical: Greenbusch Group, Inc.

Engineer - Civil: LPD Engineering PLLC; Parametrix

Engineer - Structural: Integrated Design Engineers

General Contractor: Lydig Construction  

Hardware Consultant: Adams Consulting and Estimating

Landscape Architect: HBB Landscape Architecture

Surveyor: O'Bunco Engineering Company

Transportation Consultant: Heffron Transportation, Inc.

Third party rating systems

LEED: Gold


Nancy Clanton, Clanton & Associates

Paul Mankins, FAIA, Substance Architecture

Christiana Moss, AIA, Studio Ma

Christoph Reinhart, MIT

Allison Williams, FAIA, AGWms_studio

Image credits

COTE North Transfer1

Benjamin Benschneider

COTE North Transfer2

COTE North Transfer3

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